Organic Chemistry Semester 1 LABORATORY MANUAL - Moravian ...

Nuclear Magnetic Resonance Appendix E20 Part V. Techniques and Theory
• In this case there are 2 X protons and they can produce 3 different types of
orientations with respect to B o .
Orientations Effect Probability
Shielding
1
No Effect
2
B o
Deshielding
1
∴ H A exhibits a triplet (3 peaks) H X exhibits a doublet (2 peaks)
with a total area = 1 proton with a total area = 2 proton
with relative areas of 1:2:1 with relative areas of 1:1
Out of Class Applications on NMR:
Now using the your experience with the NMR activities, the reference NMR information In
Tables 9 & 10, Figures 4 & 5 of the lab manual, CGWW pp. 258-268 and Padías Table 2-3 &
Figure 2-39 pp. 86-87 devise responses to the following:
For each of the following compounds:
a. Predict the number of different chemical shift signals that would be expected in its 1 H and
13 C NMR spectra,
b. Predict the approximate chemical shift value expected for each signal.
c. Indicate which nucleus is responsible for each signal.
(1.)
2-methoxy-2-methyl-pentanol
O CH 3
O
H
(2.)
3-methylaminopropanal
H
H
N
CH3
O
(3.)
4-iodocyclohept-2-ene-1-ol
H O
I
(4.)
2-phenyl-5-hexynoic acid
O
O
H